Roof and floor construction



' Dec. 25, 1934. J. v. KOHLHAAS 8 ROOF AND FLOOR CONSTRUCTION Filed Sept. 28, 1932 2 Sheets-Sheet l 1 10 I H II I 5 I .1 I I [I n 1| II I I 1| II V /5 II II II I I I 1 mg I""I"II"" Igg =1 I I I I I 7:. -5

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INVENTOR 12 7 Hafiz/bu Dec. 25, 1934. J, v. KOHLHAAS 1,985,786

ROOF AND FLOOR CONSTRUCTION Filed Sept. 28, 1952 2 Sheets-Sheet 2 INVENTOR r/ anwfizfiaaa I BY;

ATTORNEY My invention relatesparticularly to a buildin construction, as a floor, roof or the like, comprising a plurality of pre-i'oast slabs formed of concrete, gypsum, or other suitable material, and

5 provid d w h, inter ock n and rein p nsime s w e by the wa ;v slabs m e firml ecur d, o the rnsuppo tinga i t ue r andt diac slabs, thereby formir a; substantially monolithic surface to whichjroofing material fioore ingpr the likemay be; applied, although it will be understoodthat myinventionis also applicable to walls, partitiqns. and otherstructures which a continuouslffiin forced monolithic surface isqdesired v A In;roof orfioor statutes of its. character it has heretofore been; the practice,to provide rela t-ively; thick reinforced slabs capable of withordinarily 1 disposed directly upon the ;roof supportingstructure, and span the; spacesbetween pairs of; adjacent; steel 011- other joists therein.

Certain disadvantages;:hQWever are met in such structures, for it is apparent;-that ;the size the s wh h m co v n en lnbe handled in erectionyof theroof is necessarily limitedfor many reasons, and the supportingxjoistst must therefore be positioned at distances; from center to'center-only slightlygreater than the greatest dimension of the individual slabs; thus when, for

example, the slabs areapproximately three feet in length, the supporting joistsmllst beldisposed about three :feetapart, :even-though stress and safety factors and the like/might require only that similar joists bespacedjatintervals of six feet, and the number of joists required might be,

reduced by approximately one, half were: it not 40 sary to manufacture certain of the slabs in special sizes in order that the particulardimensions of thereof maybe conformed withdn covering the lattendue principally to thefactthat any,=appre-.

ciablecuttingiof a slab in order to fit it; properly tothe area to be coveredthereby necessarily removes all; or a larg ,1 portion, of; one or' more of the reinfor in ribs ordinarily disposed adjacent the edges of the slab,-andthus so greatly weakens it asto frequently render it unsuitable for its intended use. it

In accordance with invention, however, :I provide strong but-relatively, light slabs of subfor the limitaticnsimposedby the size of the slabs. Furthermore,when slabs provided with integral ribs are employed, it is frequently neces-s' Roommate sbs r vqu sw l j any; Kohlliaas, ministers: V, amass sspt ii'b rjjz's issg, Serial No .5,19

Samara; thickness of, a size conveniently handled and adapted to rapid and inexpensive erectionin aroof-audwhich, when erected in accordance. with the, present invention, do not requirethattheroof 9r iipor supporting 5 joists or beamsbe arranged;:closel together so as to support each slab 3, directly or that they be spaced-at shorter iiitervalsthan are required bystress andsafety factors usually relied upon for determination of, such intervals building constructiongthus, as a result io f my-invention, the architect, engineer or otherfdesigner of buildings is not restricted to thenecessity of spacing the floonorroof joists; in accordance with the length oftheslabs to be employed-J V i A principal object of my invention, therefore, is to providea roof or floor structure comprising i pre-cast slabs of light weight but of maximum strength i and having novel reinforcing means whereby relatively wi e; spans may beqcovered by precast reinforced structural elements, j-and thus a maximum load carrying capacity provided with but a minimum number of steel beams, joists or other main supportingrmembers. 7

Another gobjectof my invention is to provide convenient means whereby; adjacent slabs and other. elementsmay be easily, quickly and cheaply secured in their desired positions in the roof or floor, and thereafter firmly retained in suchposi tions against movement in anydirection. I

Afurther object of my inventionis to provide a precast structural: rib of novel form adapted for employment inthe erection of monolithic roofs,- fioors;and the like and operativeto supportthe surfaceslabsl s, i 1

. :Astillfurther object of my-invention in one of itSIOIIh-S is to provide means whereby a monolithic structure of the class aforesaid may be easily i and=cheaplyerected without the necessity of providing molds, forms orlithe like for=the pouring of jointsbe'tween' adjacent slabs; i i v 1 :Other purposes, objectsand advantages of the invention will hereinafter be more specifically rhentionedfor will 'be'apparent from the following description of certain embodiments thereof, in which reference will be had to the accompanying drawings; i

:Jn said drawingsgFig. 1 1s afragmentary top plan view, ofa portion of a roof embodying my novel elements and constructed inaccordance 50 with my preferred manner of. erection, certain. elements being. omitted for thesake of clearness; Fig; 2 is a' fragmentary-side elevation of the structure shown inlFig lyFigl 3 is an enlarged frag-j mentaryl eqtion on the lines Br-r3 inFTig. .1; Fig. 5

4 is an enlarged fragmentary end elevation of a portion of the incomplete structure shown in Fig. 1; Fig. 5 is a fragmentary top plan View of an incompleted roof portion erected in accordance with a modified embodiment of my invention; Fig. 6 is an enlarged fragmentary end section of a portion of the structure shown in Fig. 5 on the lines 6-6 in said figure; Fig. '7 is an enlarged fragmentary section on the lines 7- 7 in Fig. 5;

and Fig. is' aip'eifspective view'of a 'pre-cast slab made ina'cco'rdan'ce with my invention and which I prefer to employ in the erection of the composite structures comprehended thereby. In are-1 several figures like characters areeernployed-qtodesignate the same parts, and the several sections" are taken in the direction of the arrows in the section lines- Referring now more particulatl are."

the course of erection on a building in which steel beams S form theroof'supportaI provide in ac cordance"with my invention pre-cast ribs 1 of novel character-which maybe formed of concrete, orany other suitableinateriaLand desirably have one or more stem reinforcing ro'ds'2"embedded therein and extending "longitudinally thereof; these ribs are employed to support the roof slabs and are disposed atsuitable-distances apart with their'ends resting on-tl'ie beams S. The ribs are preferably rabbettedat each end as at 3 to fit partly over and partly between adjacent beams,

whereby the ribsl are held against longitudinal movement, even before theyare permanently secured to the beams. For thispurpose'any convenient means may be employed, such, for example, as the steel'plates 5, 6 held together by mean s'of a bolt 8, passing through the beam flange, and nut 9. The lower plate 6 is desirably flanged at two'of its edges as shown in Fig. 4, the flanges being effective to restrain any tendency of the ribs to move or creep transversely, that is, longitudinallyof'the steel beams;

After the ribs 1" have been secured to the beams at the. proper distances asfldetermined by the lengthofthe slabs tobe employed,'suitable' concrete surface slabs may then be laid in place,-resting'on'th'e ribs, and forthi'spurpose I-prefer to employ-my improved slabs '10 the respective ends of which are'suitably'rabbetted as at 11 to permit them to be fitted to theribs, as is clearly shown In Figs.'3= and 4'.'*One' orboth of the longitudinal edges of .each slab 10 "are desirably slightly bev eled as at 12 =fora purpose which-will hereinafterappear, and embedded-in each slab and extending longitudinally thereof are a plurality of' r'e in' forcing rods 13. While I have shown in thedrawings-two .rods 13 in each slab; it: will be-understood thatone only or any greater number of such" rods maybe employedas desired, usuallydepend ingon the width of. the slab. The projecting ends of each rod 13 are bent approximately at right angles a short/distance ,from the, ends of the slabs,,j and thus when the latter are. in place on; theiribathe rod ends 13 extend partially over and.

then; upwardly; from theribs, the rods from the, slabs,on,oppositesidesof any rib overlapping to. provide a plurality of small spaced cradles into which a:tie-.rod 14 may beiloweredto lock the slabstogether; The tie rods 14 may thereafter be secured in place bywires 15, extending under the plates 5 and twisted together above the tie'rods. ASfWfll'bG understood from reference to Fig. 3, theends'ofadjacentslabs 10 and the top of thein common'supportingrib lc'obperate to form a trough-or: groove l7 into whiclr-the slab 'reinforc-' lshowing an incompleted portion of a roof structure in ing rods project to receive the tie rod, and as at least one of the longitudinal edges of each slab is preferably beveled, it is desirable that the slabs be so placed that additional grooves or troughs 18 will be formed by the abutting longitudinal edges of adjacent slabs, as between two beveled edges or between one beveled edge and an adjacent square edge.

The slabs having been laid in position and the tie rods 14 properly placed and secured to the plates 5, a cement or concrete mix, orany other suitably impermeable grouting material, is then introduced into the grooves 17, 18 in accordance with the usualpractice, and allowed to harden,

thus binding theslabs together in a continuous layer "of concrete, if that be the material em- .;.ployed, while the interlocking of the reinforcing In the form of my invention shown in Figs. 5,

6 and 7 I provide in the ribs reinforcing rods 19 having upturned ends similar to those of the slab reinforcing rods 13 already described so that the ends of the rods in adjacent ribs overlap to form a cradle adapted to receive a tie rod 14 and thus the ribs are locked securely in place, while the' tie rods 14 may be secured to the tie rods 14' by any suitable means, such as a wire 20'; threaded eyes 21 are also desirably provided at suitable spaced points along the steel beams S for secu'ring the tie rods 14' thereto whereby a'continuous interlocked network of reinforcing rods extends throughout the roof area and is firmly held inf place at spaced points through connection with the supporting structure formed by the subjacent beams S.

' To complete the monolithic'character of the roof in this form of the invention, I prefer to place temporary side forms 22 along each steel beam to provide, as shown in Fig. 6, a trough through whichthe adjacent tie rod 14' extends and into which grouting may be poured to there-' by enclose all metal parts above the steel beam within the concrete or other grouting material and securely hold them in place in the roof structure. After the grouting in the trough has set and hardened, the side forms 22 may, and usually will, be removed.

It is apparent that when the dimensions of the roof or floor are such that certain slabs smaller than standard sizes are required, they may readily be obtained by suitably cutting standard slabsto the, required dimensions and bending the reinforcing rods, the uniform thickness of the standard slabs permitting such cutting withou V the sacrifice of strength.

While I have herein shown and particularlydescribed certain specific forms of my invention ascomprised in roof structures, it will be understood that I do not desire or intend thereby to "limit myself thereto, as the same may with equal facility be employed for floors, while changesin the size and proportions of the various elemerits employed, and in the form and arrangement thereof may be made if desired without than departing from the spirit and scope of the invention as defined in the appended claims.

Having thus described my invention, -I claim and desire to protect by Letters Patent of the United States:

1. A building construction of the character described comprising spaced joists, spaced precast monolithic ribs supported thereby, each rib having a reinforcing rod extending therethrough and projecting beyond its extremity, said rods overlapping the projecting ends of the rods in adjacent ribs, means extending transversely to said rods operative to tie said projecting ends together, a plurality of precast slabs supported on the ribs, a reinforcing rod in each slab projecting beyond the extremities thereof and overlapping the projecting ends of the rods in adjacent slabs, and means extending transversely of said last mentioned rods operative to tie said rods together.

2. A building construction of the character described comprising spaced joists, spaced precast monolithic ribs supported thereby, each rib having a reinforcing rod extending therethrough and projecting beyond its extremity, the projecting ends of the rods extending substantially normal to the main portion thereof, said rods overlapping the projecting ends of the rods in adjacent ribs, means extending transversely to said rods operative to tie said projecting ends together, means operative to tie said first mentioned means to the adjacent joists, a plurality of precast slabs supported on the ribs, a reinforcing rod in each slab projecting beyond the extremities thereof,

the projecting ends of the rods being normal to the main portions thereof and overlapping the projecting ends of the rods in adjacent slabs, means extending transversely of said last mentioned rods operative to tie said rods together, means operative to secure said last mentioned means to said first mentioned means, and grouting material substantially imbedding all of said means and presenting an uninterrupted monolithic surface continuous with the upper surfaces of the adjacent slabs.

JOHN V. KOHLHAAS. 

